The terrestrial ecology, as well as the coastal and marine ecosystems, can benefit from the process of restoring and rewilding islands that have been devastated by harmful invasive species. A miniature for the unmet potential of ecosystem restoration on a global scale, the linking of land and water through coordinated conservation efforts may bring unrealized and magnified advantages for biodiversity, human well-being, climate resilience, and ocean health. Today’s conservationists recognize the need of preserving entire ecosystems rather than just parts of them, and are shifting away from the traditional practice of treating each ecosystem as an isolated unit.
A new viewpoint, “Harnessing island-ocean connections to maximize marine benefits of island conservation,” published on December 5 in the Proceedings of the National Academy of Sciences (PNAS), acknowledges the crucial link between island and marine ecosystems and recognizes island and near-shore marine environmental features that promote strong associations in these ecosystems worldwide. Using this framework, governments, foundations, indigenous peoples, local communities, non-governmental organizations (NGOs), and conservationists may make land-sea conservation and management choices that strengthen ocean health and benefit islands.
UC San Diego marine ecologist and perspective author Stuart A. Sandin, Ph.D., explains how this information can be applied to islands all over the world to better understand the marine benefits of island restoration projects and increase the returns on investments made in conservation management for the benefit of humans, other animals, and the planet.
Some of the most unique and valuable ecosystems on Earth may be found on islands, which are home to a surprising amount of endemic species. “Connector species,” such as seabirds, seals, and land crabs, promote the exchange of nutrients between the ocean and islands, which is essential for the health of land-sea ecosystems. Larger fish populations, faster-growing coral reefs, and higher rates of coral recovery from climate change impacts are all linked to islands with higher seabird populations. Seabirds forage in the wide ocean and deliver enormous quantities of nutrients to island ecosystems through their guano deposits.
However, many seabird species have been wiped out or are in danger of extinction because of the presence of non-native creatures such as rats on islands where the birds breed and consume the birds’ eggs and hatchlings. When these “link” species become extinct, entire terrestrial and marine ecosystems can collapse. One of the finest instruments for restoring native plant and animal life and ecosystems is the elimination of invasive species on islands.
Penny Becker, Ph.D., vice president of conservation at the charity Island Conservation, and a coauthor on the paper stated that islands and seas are connected-something many people living along coasts have long known, depended on, and managed holistically because of. Connecting land-based initiatives, such as eradicating invasive species, with marine restoration and conservation has a substantial appealing vision for protecting and restoring islands and coastal areas.
The authors’ combined expertise can guide decisions on where on restored islands marine co-benefits will have the most impact. They emphasize six important environmental characteristics—precipitation, elevation, plant cover, soil hydrology, oceanographic productivity, and wave energy—that might lead prioritization of island-ocean restorations.
Floreana Island in Ecuador’s Galapagos Archipelago is one example of a high-potential island for producing substantial marine co-benefits after invasive species removal and island rewilding because of its higher rainfall, lower wave energy, and other conditions consistent with high land-sea connectivity.
Wes Sechrest, Ph.D., co-author and chief scientist and CEO of the charity Re:wild said that this data is tremendously beneficial for deciding where to spend conservation work and precious resources to have the biggest impact. The researchers now know that restoring and rewilding Floreana Island will not only benefit species on the island and in the neighboring Marine Protected Area, but will also provide climate resilience for the region. This is vital in creating a healthy planet for all species on Earth as well as a sustainable Floreana for the indigenous islanders.
Floreanans have seen the destructive impacts of invading species directly over the course of decades, and now they play a vital part in the island’s recovery.
A second location with promising land-sea connections is Sonsorol Island in Palau. The decline in seabird populations caused by invasive species has greatly reduced nutrient deposition, which in turn has reduced the productivity of reefs in the area. Due to the island’s isolation, residents of Sonsorol must rely primarily on their own resources. Before the arrival of invasive species, the people of Sonsorol Island coexisted with their environment and prospered off the island’s plentiful natural resources.
According to Kate Brown, executive director of the Global Island Partnership and co-author, Sonsorol and Floreana Island are only two of the numerous islands that hold significant potential for restoring marine habitats. A major win for marine and terrestrial biodiversity might come from making island restoration a global priority. With your help, we can create island settlements that can withstand natural disasters thanks to thriving marine and island ecosystems.
Sandin, Stuart A. (2022). Harnessing island–ocean connections to maximize marine benefits of island conservation, Proceedings of the National Academy of Sciences. DOI: 10.1073/pnas.2122354119. doi.org/10.1073/pnas.2122354119